1,042 research outputs found
The Quest for the Heaviest Uranium Isotope
We study Uranium isotopes and surrounding elements at very large neutron
number excess. Relativistic mean field and Skyrme-type approaches with
different parametrizations are used in the study. Most models show clear
indications for isotopes that are stable with respect to neutron emission far
beyond N=184 up to the range of around N=258.Comment: 4 pages, 5. figure
Spatial-temporal structure of seismicity of the North Tien Shan and its changeunder effect of high energy electromagnetic pulses
The effect of high-energy electromagnetic pulses emitted by a magnetohydrodynamic generator used as a source for deep electrical sounding of the crust on spatial-temporal structure of seismicity of the North Tien Shan is explored.
Five-six years periodicity of changes in spatial distribution of seismicity was revealed. The effect of electromagnetic
pulses increases the stability of the spatial distribution of seismicity over time and simultaneously speeds up cycles of its transformations, which develop on stabilization background. Increasing of seismic energy release after electromagnetic impacts is observed basically in most active zones. Periodic variation of efficiency of earthquakes triggering on the distance to the MHD-generator was detected. It was shown that electromagnetic pulses give rise to an appreciable increase in the rate of local earthquakes, occurring around 2-6 days
after the pulses. Total earthquakes energy released after start-ups was by 2.03·1015 J greater than the energy released
before them. At the same time, the total energy transmitted by the MHD-generator was 1.1·109 J, i.e. six orders of magnitude smaller. Consequently, the electromagnetic pulses initiated the release of the energy that had been stored in the crust due to activity of natural tectonic processes in the form of comparatively small earthquakes,
which leads to an additional release of tectonic stresses
Fractional Systems and Fractional Bogoliubov Hierarchy Equations
We consider the fractional generalizations of the phase volume, volume
element and Poisson brackets. These generalizations lead us to the fractional
analog of the phase space. We consider systems on this fractional phase space
and fractional analogs of the Hamilton equations. The fractional generalization
of the average value is suggested. The fractional analogs of the Bogoliubov
hierarchy equations are derived from the fractional Liouville equation. We
define the fractional reduced distribution functions. The fractional analog of
the Vlasov equation and the Debye radius are considered.Comment: 12 page
Banks-Zaks fixed point analysis in momentum subtraction schemes
We analyse the critical exponents relating to the quark mass anomalous
dimension and beta-function at the Banks-Zaks fixed point in Quantum
Chromodynamics (QCD) in a variety of representations for the quark in the
momentum subtraction (MOM) schemes of Celmaster and Gonsalves. For a specific
range of values of the number of quark flavours, estimates of the exponents
appear to be scheme independent. Using the recent five loop modified minimal
subtraction (MSbar) scheme quark mass anomalous dimension and estimates of the
fixed point location we estimate the associated exponent as 0.263-0.268 for the
SU(3) colour group and 12 flavours when the quarks are in the fundamental
representation.Comment: 33 latex pages, 25 tables, anc directory contains txt file with
electronic version of renormalization group function
Production cross sections of neutron rich isotopes from a 82Se beam
Production cross sections for neutron-rich nuclei from the fragmentation of a
82Se beam at 139 MeV/u were measured. The longitudinal momentum distributions
of 122 neutron-rich isotopes of elements were determined by
varying the target thickness. Production cross sections with beryllium and
tungsten targets were determined for a large number of nuclei including several
isotopes first observed in this work. These are the most neutron-rich nuclides
of the elements (64Ti, 67V, 69Cr, 72Mn). One event was
registered consistent with 70Cr, and another one with 75Fe. A one-body Qg
systematics is used to describe the production cross sections based on thermal
evaporation from excited prefragments. The current results confirm those of our
previous experiment with a 76Ge beam: enhanced production cross sections for
neutron-rich fragments near Z=20.Comment: Talk given at the 11th International Conference on Nucleus-Nucleus
Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1, 2012. To appear
in the NN2012 Proceedings in Journal of Physics: Conference Series (JPCS
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